Method of treating rails to prevent oil films



June 16, 1959 I Y R. K. ALLEN 2,890,970

METHOD OFTREATING .RAILS TO PREVENT OIL FILMS Filed July 23. 1954 [)7 win tor: Rab art A. A/Ven,

is Attarney United States Patent .METHOD OF TREATING RAILS TO PREVENT OIL FILMS Robert K. Allen, Erie, Pa., assignor to General Electric Company, a corporation of New York Application July 23, 1954, Serial No. 445,246

11 Claims. (Cl. 117--49) My invention relates to the removal and prevention of thin oil films on the wear bands of rails and more particularly to the phenomena caused by oil films of wheel slippage of the driver wheels on a locomotive and poor electrical contact between the wheels and rails over certain known portions of the track.

The invention is based on my discovery of the existence of microscopically thin oil films on the wearing surface of the railhead. These thin oil films greatly reduce the adhesion as well as the electrical conductivity between carwheels and the rail. This is particularly detrimental when the driver wheels of the locomotive are prevented from contacting the rails. "The films themselves are formed from oil deposits which may contain silica, iron, iron oxide which are present in the railhead in certain locations. Under conditions of high relative humidity where/there are grease deposits present, a thin, nearly invisible, layer of oil will spread over the highly polished wearingsurface of the railhead. These films are only a few molecules in thickness and may contain oxide and silica dust which is often as small as two microns in diameter. The oil creeps from the grease deposits and action described above.

If any heavy oil deposit on the side of the railhead is contacted by water, some of the oil will float on the surface of the water. When. the water is removed, the oil film isleft on the rail. However, this type of oil film is not especially slippery. These heavy oil deposits on the side of the rail contain a certain amount of journal oil thathas been partially oxidized. This material will not float, but when it contacts moisture or dew, it will literally chase the water from the metal surface and thus spread rapidly over the polished wearing surface.

This action is not floating of the oil, but rather surface tension and adhesion equilibrium between these interfaces: water andsteel, oil and steel, and oil and water. Forwant of a better name, I call thisffilm creepage.

,It'has been found that the creepage phenomenon is, with regard to metals, most pronounced on highly polished moist surfaces. Consequently, the slippery films are formed most quickly on this type of metal surface. It should be noted that the wearing surface of mainline railis always highly polished except for occasional pit marks. if r It has been found that a thin layer of water will be pushed from a levelpolished metal surface at any time the oxidized journal oil touches the water and the metal.

This is explained by the greater adhesion of this oil to the metal. The result is that a slippery film of oil capable of supporting a locomotive remains in direct contact with the metal surface.

For many years the railroad industry has employed sand to condition the surface of the rail. and give satisfactory adhesion. On foggy. mornings, the engineman while running over a certain section of track, would always apply sand over known slippery track. This practice has never directly attacked the thin film or heavy oil deposits present on the railhead, but instead deposits a granular layer of sand on the rail. The locomotive wheels cause the individual grains of sand to cut through the thin film due to very high pressures per square inch, thereby giving the required adhesion. This solution is of limited value on films which vary because of atmospheric conditions, oil and grease accumulations, frequency of tracks use, etc. The use of sand causes rapid wear and damage to moving truck parts, traction motors, and other items of the running gear. Another disadvantage of the use of sand is the high train rolling resistance because the remainder of the train must roll over the sand deposited by the locomotive. Sand also causes packing and solidification of track ballast, fouling oftrack circuits, and the need for special maintenance on switches and crossovers.

Therefore, the object of my invention is a method of treating the rail running surface to keep it in an oil film free condition without damage to the vehicles or road bed.

A further object of my invention is a method of removing, the rail oil films to improve the rail adhesion for driving or braking a locomotive or car and to improve the electrical contact between wheels and rails for proper signal operation without damage to the track, ballast, or track signalling and switching apparatus.

A most effective way to prevent the formation of slippery insulating rail films is to prevent any oil from reaching the railroad tracks. However, this is not practicable with modern railroading since all vehicles have moving parts which must be lubricated in some manner. A major source of oil on the rails is from journal box leakage which creeps down the outer wheel face and onto the wheel treads. This oil on the treads is deposited on the outer edge of the railhead at frogs, switch points, the low rail of wide gauge curves, and any other point where the outer portion of the wheel tread touches the rail. The improving of journal box oil seals to prevent oil leakage and maintenance of correct track gauge so that the oil does not deposit on the railhead would help immeasurably in reducing the amount of oil reaching the track surface, but this solution is neither complete nor economically feasible.

In carrying out my invention in one form, I have developed a method for preventing the thin oil film by the application of a water repellent or hydrophobic material to the wearing surface of a clean rail. Tanks containing active ingredients including detergents, solvents, alcohols, silicone compounds, or fluorinated organic acid compounds such as perfluorobutyric acids, are placed in the locomotive. When it is necessary to clean the rails, the detergents, alcohols or solvents are applied to the rail. The silicone compounds and fluorinated acid compounds are then applied to the clean rail to make a water repellent film on the track. The use of these compounds has been found .to prevent the oil film creepage on a running surface which has been treated by these compounds once every few days. I prefer to apply these materials to the rail in a thin film by atomizing, wiping or spraying the material over the rail as the locomotive passes over it, although the application of the material on the running tread ofthe wheel or of "the rail has been found satisfactory.

For a more complete understanding of my, invention reference should be had to the following detailed specification taken in conjunction with the accompanying drawings in which:

Fig. .1 is a side view partially cut off of a locomotive showing two containers of active solution;

Fig. 2 is an end view of the locomotive showing means for applying materials directly to the wheel tread; and

Fig. 3 shows grease deposits on an enlarged rail car wheel.

Referring now to the drawing, in one form of my invention I provide a container 1 secured to a portion of a rail vehicle such as a locomotive 2 having a feed line 3 that extends to a region in proximity with the railhead 4. The feed line 3 is supported at its lower end by a bracket 5 which is attached to the truck frame 6.

One method of applying the water repellent material to the clean wearing surface of the railhead 4 is to .pass a small high velocity air stream from a supply tank past a small opening hydraulically connected to the supply of fluid in the tank 1 so that a small amount of fluid is atomized and then passed at a considerable velocity through the feed line 3 to the region of the railhead where it is deposited in minute quantities along the railhead as the locomotive proceeds down the track. To maintain the particles in the region over the running surface so that they may settle thereon, a nozzle 7 is provided on the end of the feed line.

The material applied prevents the formation of slippery films thereby rendering the wheel and rail surfaces inert to creepage action of these films. Materials that are satisfactory for this purpose are silicone compounds such as methyl silicone oil (998lLTNV-4Q) and fluorinated acid compounds which leave the wearing surface water repellent or hydrophobic to prevent the formation of a film of water thereon capable of serving as a vehicle facilitating oil creepage. Depending on the proportion of active ingredient in the vehicle used to spread the agent, the saturation of the air in the feed line by particles of fluid could be increased to such an extent that a spray was actually used instead of the atomized gas I have discussed above. It is proposed that the material be placed on the rail at frequent intervals of time to keep the rail free of the oil film for the entire period the rail is being used instead of the alternative method now used of applying sand to the railhead when it is known that the running band will be slippery. In this manner, the locomotive or train caboose can be run at ordinary speeds without wheel slippage while applying this material one or two times a day if necessary to the section of the rail where slippage may occur. However, it is more likely one of two applications a week will be preferable.

Also in Fig. l, I have shown an alternative method for applying water repellent material directly to the clean rail by wiping it on. This method utilizes a container 11, a feed line 12, and a bracket 13 attached to the truck frame 6 and a pad 14 of some sort at the end of the feed line 12 for applying the water repellent material directly to the wearing surface of the rail 4 by wiping it on in a manner similar to the application of wax on a car with a damp cloth. It is preferred that the active ingredient drip from the container into the feed line at a rate that does not over saturate the pad 14. The frequency of the drip, of course, will depend on the speed of the locomotive 2 as well as the condition of the track.

To operate properly the pad 14 should be made of a porous material that will withstand considerable friction. Some of these materials include felt wicking and sintered products of various types. The operation of this particularmethod does not depend entirely on the pad 14. If the pad were omitted or destroyed, the drip feed would still work properly as long as the feed line 12 were positioned over the wearing surface of the rail so that the drip would be onto the wearing surface and the various wheels of the train along with the natural creepage of the material will spread the material over the entire wearing surface to give the desired protection.

In Fig. 2, I have shown other methods of applying the active ingredients to the rail. The container 15 supplies water repellent fluid through the feed line 16- to a pad 17 mounted on the bracket 18 which is attached to the truck frame 6. The pad 17 contacts the running tread of wheel tire 19 and should be a material similar to the pad 14 so that it will stand up under the friction involved. Applying the Water repellent material to the wheel tread 19 as shown in Fig. 2 is equivalent to applying it to the rail. However, the pad 17 receives less wear because of the uneven joints that will be encountered by the pad 14 as it slides on the rail. The effect in preventing film creepage is the'same with either application. The material placed on the wheel tread is deposited in a thin layer over the wearing surface of the rail as effectively as that placed directly on the rail 4. g

Also in Fig. 2 I have shown a container 20 having a feed line 21 that is positioned over the wheel by a bracket 22. The material may dripfrom the feed line to, the Wheel tread. This method givm results similar to that where the pad 17 is wiped on the wheel. At high speeds, however, the liquid drops of the drip feed system are thrown from the wheel so that a large percentage of the active ingredient may be lost. If it is desired that this method be used at relatively high speeds, the vehicle of the active ingredient should be made sticky and viscous. At relatively low speeds, up to 5 miles per hour, this problem is of no consequence.

Fig. 3 shows how the oil of a journal bearing 24 coats a car wheel 25. The phantom wheel 26 shows how this grease coating or crater compound 27 is deposited on the low rail of a wide gage curve. A similar phenomenon occurs at frogs and switches where the wearing surface changes its shape enough to cause the grease coating 27 to touch on the railhead. I

Up to this point I have disclosed means for preventing the oil film from occurring on the clean railhead 4. However, since I have discovered that this rail oil film is the underlying problem of wheel slippage and poor signalling, and has been a special problem since the advent of electric and diesel electric locomotives which are able to deliver higher tractive effort to the driving axles driven individually, I have also developed a method for applying active ingredients to destroy the thin slippery film once it has formed and remove the grease deposits from which it creeps. This is a necessary part of treating the rail and will of itself prevent the film fora short time. The application of solutions containing detergents, solvents or alcohols will remove the film and, if properly utilized, the grease deposits from which it creeps. Such an application of cleaner will be of particular value in regions where it is not practical for some reason to keep the rail film free by coating the rail with unwettable compounds. The frequency of application should be controlled by the conditions on particular track involved.

For relatively heavy layers of grease or for regions where heavy layers of oil film are mixed with the thin film, I prefer to use a petroleum base emulsifying detergent such as Oa'kite #8 (mixed 1 to 4 with petroleum spirits) or Enthone #75, a petroleum solvent cleaner detergent, applied by the feed line 3 with the locomotive going at a relatively slow speed such as 2 miles per hour, when the feed lines 3 and 12 are 20 feet apart, and a saturated steam rinse being applied through the feed line12 to remove the emulsified oil that is created 'or left by the emulsifying agent. If the elimination of the oil film is incomplete, the rail adhesion will not be at its maximum value. However, aqueous solutions of alkaline detergents such as Qakite #92 or Pennsalt K-2 will eliminate the residue. When applied with steam, the alkaline detergent solutions alone will eliminate light accumulations of oil such asjournal leakage.

The cleaning apparatus also may be'mounted on a car that is present in the train either ahead or behind the locomotive. When ahead of the locomotive, it will clean the rails for that particular train. If used ahead of the driving wheels, rinsing must be complete to remove all of the emulsified oil; If behind the locomotive, as in a caboose, it will clean the rails for the next train.

After the rail has been cleaned and dried, it may be treated with a material such as those previously described which renders the rail unwettable. The same car or locomotive can do the cleaning and also do the treating of the rail provided the rail has reasonably dried. The wearing surface may be artificially dried by heat from a flame heater 23 or from other heaters (not shown) mounted on the train or on. the rails at frogs, switches, etc. In fact, I have found that an intense flame will remove the oil films without other cleaning. However, this consumes considerable fuel when there is much grease present. i

As has been mentioned before, railroad enginemen generally know where the locomotive is likely to slip under certain known conditions. The past practice has been to apply sand over these regions to get the required adhesion. It is proposed that this treatment of cleaning with a detergent and/ or applying a water repellent substance on the wearing surface be used periodically in these regions, thus eliminating the use of sand with its damaging effects.

While I have shown and described particular embodiments of my method for removing the thin oil film, it will be understood, of course, that I do not wish to be limited thereto since many modifications may be made and I therefore contemplate by the appended claims to cover any such modifications as may fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A method of treating the wearing surface of a railhead thereby to improve traction of a train thereon by preventing creepage of oil films over the Wearing surface from deposits of grease on the railhead, comprising applying a petroleum grease and oil emulsifying detergent to the railhead to clean the wearing surface, applying a hydrophobic substance in liquid form to the wearing surface to form a thin water repellent film to prevent the adhesion of a film of moisture thereon to serve as a vehicle facilitating oil creepage.

2. A method of treating a railhead that also serves as an electric conductor to remove deposits of grease and resulting slippery films of oil spreading therefrom over the wearing surface of the railhead comprising spraying the railhead with a petroleum base emulsifying detergent solution, spraying the railhead with steam to remove the emulsifying detergent solution and the grease and oil suspended therein, spraying the railhead with an alkaline detergent solution, spraying the railhead with a steam rinse to remove any residue from the rail, and applying heat to the railhead to dry the wearing surface.

3. A method of treating the wearing surface of a railhead that also serves as an electric conductor to remove and prevent the formation of films of insulating oil thereon clue to creepage of oil films over the wearing surface from deposits of grease on the railhead, comprising spraying the railhead with a petroleum base emulsifying detergent solution, spraying the railhead with saturated steam to remove the emulsifying detergent solution and the grease and oil suspended therein spraying the railhead with an alkaline detergent solution followed by a saturated steam rinse to remove any residue from the rail, applying heat to the railhead to dry the wearing surface, and applying a hydrophobic substance in the liquid form to the wearing surface to form a thin water repellent film thereon thereby to prevent the formation '6 of a film of moisture on the wearing surface which serves as a vehicle facilitating oil creepage.

4. A method of treating members subject to transfer energy by rolling friction where one member is driven to have a surface roll on a surface of another member, to increase the traction therebetween' by destroying a film containing oil on the contacting surfaces, comprising the steps of applying an oil emulsifying detergent to the surface of the member which is driven, and rotating the driven'member to apply said detergent. to the surface of the other member.

5. A method of eliminating oil films from a railhead that also serves as an electric conductor to improve the rail adhesion and to improve the electric contact between the wearing surface of the rail and rail vehicle wheels, comprising the steps of applying an oil emulsifying detergent to the running tread of a rail wheel, and rotating the wheel to apply said detergent to the wearing surface of the railhead.

6. A method of eliminating oil films from the Wearing surface of a railhead that also serves as an electric conductor to improve the rail adhesion and to improve the electric contact between the wearing surface of rail and the rail vehicle wheels, comprising the steps of Wiping an oil emulsifying detergent on the running tread of a rail wheel, and rotating the wheel to transfer said detergent to the Wearing surface of the railhead.

7. A method of eliminating oil films from the wearing surface of a railhead that also serves as an electric conductor to improve the rail adhesion and to improve the electric contact between the wearing surface of rail and the rail vehicle wheels, comprising the steps of spraying an oil emulsifying detergent on the running tread of a rail wheel, and rotating the wheel to transfer said detergent to the wearing surface of the railhead.

8. A method of treating the wearing surface of a railhead that also serves as an electric conductor to eliminate and prevent oil films thereon and thus to improve the rail adhesion and to improve the electric contact between the wearing surface of the rail and rail vehicle wheels, comprising the steps of applying an oil emulsifying detergent to the railhead thereby to eliminate the oil film, and applying a water repellent substance of the group consisting of silicone compounds and fiuorinated organic acid compounds to the wearing: surface of the railhead thereby preventing the formation of a film of water on the wearing surface which would serve as a vehicle facilitating oil film creepage.

9. A method of treating the wearing surface of a railhead that also serves as an elmtric conductor to eliminate and prevent oil films thereon and thus to improve the rail adhesion and to improve the electric contact between the wearing surface of the rail and rail vehicle wheels, comprising the steps of applying an oil emulsifying detergent to the running tread of a rail Wheel, rotating the wheel to apply said detergent to the wearing surface of the railhead thereby to eliminate the oil film, and applying a water repellent substance of the group consisting of silicone compounds and fiuorinated organic acid compounds to the wearing surface of the railhead thereby preventing the formation of a film of Water on the wearing surface which would serve as: a vehicle facilitating oil film creepage.

10. A method of treating the Wearing surface of a railhead that also serves as an electric conductor to eliminate and prevent oil films thereon and to improve the rail adhesion and to improve the electric contact between the wearing surface of the rail and rail vehicle wheels, comprising the steps of wiping an oil emulsifying detergent on the running tread of a rail. wheel, rotating the wheel to transfer said detergent to the wearing surface of the railhead thereby to eliminate the oil film, and wiping a water repellent substance of the group consisting of silicone compounds and fluorinated organic acid compounds on the wearing surface of the railhead thereby to prevent the formation of a film of water on the Wearing surface which would serve as a vehicle facilitating oil film creepage.

11. A method of treating the wearing surface of a railhead that also serves as an electric conductor to eliminate and prevent oil films thereon and to improve the rail adhesion and to improve the electric contact between the wearing surface of the rail and rail vehicle Wheels, comprising the steps of spraying an oil emulsifying detergent on the running tread of a rail Wheel, rolling the wheel on the railhead to transfer said detergent to the wearing surface of the railhead thereby to eliminate the oil film, and spraying a water repellent substance of the group consisting of silicone compounds and fluorinated organic acid compounds on the Wearing surface of the railhead thereby to prevent the formation of a film of water on the wearing surface which would serve as a vehicle, facilitating oil film creepage.

References Cited in the file of this patent UNITED STATES PATENTS Smyth Aug. 26, Tuttle Dec. 22, Libbey June 19, Johnson Feb. 25, Caprcz Dec. 22, Nachtman Mar. 27, Campbell Apr. 30, Szatyn -2 Apr. 30, Barry Aug. 20, Barry May 10, Wittner July 12, Smith-Johannsen June 24, Underwood et a1. Sept. 23,

OTHER REFERENCES Organic Finishing, vol. 14, No. 5, May 1953, article 20 by J. E. Hyler (pages 7-10). 

1. A METHOD OF TREATING THE WEARING SURFACE OF A RAILHEAD THEREBY TO IMPROVE TRACTION OF A TRAIN THEREON BY PREVENTING CREEPAGE OF OIL FILMS OVER THE WEARING SURFACE FROM DEPOSITS OF GREASE ON THE RAILHEAD, COMPRISING APPLYING A PETROLEUM GREASE AND OIL EMULSIFYING DETERGENT TO THE RAILHEAD TO CLEAN THE WEARING SURFACE, APPLYING A HYDROPHOBIC SUBSTANCE IN LIQUID FORM TO THE WEARING SURFACE TO FORM A THIN WATER REPELLENT FILM TO PREVENT THE ADHESION OF A FILM OF MOISTURE THEREON TO SERVE AS A VEHICLE FACILITATING OIL CREEPAGE. 